• ALGAE
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• v.33 no.1
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• pp.109-125
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• 2018

Turkish towel (Chondracanthus exasperatus), Pacific dulse (Palmaria mollis, also known as Red ribbon seaweed), and sea lettuce (Ulva spp.) were cultivated in a land-based intensive culture system at the Manchester Research Station, USA from August 2013 to September 2014. Macroalgae were grown in tumble-aerated tanks, harvested bimonthly for seasonal growth calculations, and analyzed for protein, lipid, ash, and amino acid content. Growth rate of all three species exhibited a similar pattern, with the highest specific growth rates occurring during the summer months (Turkish towel: 7.8%, Pacific dulse: 8.2%, and sea lettuce: 6.2%). Growth of all three species was lowest around winter solstice; with negative growth only observed in sea lettuce. On a dry weight basis significant differences in protein content existed between the three species with highest values for sea lettuce ($29.5{\pm}1.4%$). Lipid content varied between species (0.95-2.78%) with significantly higher lipid observed in sea lettuce (0.58-4.82%). No significant differences were detected on a seasonal basis among each species. Essential amino acids accounted for $43{\pm}0.9$ to $47{\pm}1.2%$ of total amino acids with Turkish towel having the highest value. Turkish towel had a significantly higher taurine level ($0.82{\pm}0.27$) than the other macroalgae. The levels of persistent organic pollutants and heavy metals were low. The estimated annual product of the three species ranged from 50- to $70-mt\;dry\;weight\;ha^{-1}\;y^{-1}$, significantly higher than conventional crops. Land-based culture of these species can produce year-round harvest, consistent product quality, and low contaminant levels.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.254-260
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• 2016

Doenjang samples were prepared by inoculation of multiple starters consisting of two Bacillus spp., one yeast, and one fungus. Doenjang A was fermented with Bacillus amyloliquefaciens EMD17, B. amyloliquefaciens MJ1-4, Pichia farinosa SY80, and Rhizopus oryzae. Doenjang B and C were fermented with the same yeast and fungus but different Bacillus strains; namely, B. amyloliquefaciens EMD17 and B. subtilis CH3-5 for doenjang B, and B. amyloliquefaciens MJ1-4 and B. subtilis CH3-5 for doenjang C. Doenjang D was fermented with microorganisms present in rice straw (control). The doenjang samples were spiked with B. cereus ATCC14579 at two different levels, 10⁴ CFU/g doenjang (I) and 10⁷ CFU/g doenjang (II). All eight doenjang samples were fermented for 70 days at 25℃. Growth of B. cereus was inhibited in doenjang A, B, and C, with the bacterial cell count after 70 days being less than the initial 10⁴ CFU/g added, whereas B. cereus was not inhibited in doenjang D. Doenjang B showed the strongest inhibitory activity against B. cereus, with a cell count of less than 10³ CFU/g after 42 days, even when B. cereus was initially added at 10⁷ CFU/g. Some properties of the doenjang samples, such as pH, TA, and amino-type nitrogen content, were similar to those of doenjang fermented with starters only. The results indicate that carefully selected starters can effectively prevent the growth of B. cereus during doenjang fermentation.

• The Plant Pathology Journal
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• v.35 no.6
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• pp.662-673
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• 2019

Root-knot nematodes (RKNs) are among the most destructive plant-parasites worldwide, and RKN control has been attempted mainly using chemical nematicides. However, these chemical nematicides have negative effects on humans and the environment, thus necessitating the search for eco-friendly alternative RKN control methods. Here, we screened nematicidal lactic acid bacteria (LAB) isolated from kimchi and evaluated their efficacy as biocontrol agents against RKNs. Of 237 bacterial strains, Lactobacillus brevis WiKim0069 showed the strongest nematicidal activity against the second-stage juveniles (J2) of Meloidogyne incognita, M. arenaria, and M. hapla and inhibited the egg hatch of M. incognita. The culture filtrate of WiKim0069 had a pH of 4.2 and contained acetic acid (11,190 ㎍/ml), lactic acid (7,790 ㎍/ml), malic acid (470 ㎍/ml), and succinic acid (660 ㎍/ml). An artificial mixture of the four organic acids produced by WiKim0069 also induced 98% M. incognita J2 mortality at a concentration of 1.25%, indicating that its nematicidal activity was derived mainly from the four organic acids. Application of WiKim0069 culture filtrate suppressed the formation of galls and egg masses on tomato roots by M. incognita in a dose-dependent manner in a pot experiment. The fermentation broth of WiKim0069 also reduced gall formation on melon under field conditions, with a higher efficacy (62.8%) than that of fosthiazate (32.8%). This study is the first report to identify the effectiveness of kimchi LAB against RKNs and to demonstrate that the organic acids produced by LAB can be used for the RKN management.

• Korean Journal of Veterinary Research
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• v.46 no.4
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• pp.337-345
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• 2006

The shigellae are common etiological agents of bacillary dysentery in humans and primates. During four years from 2002 to 2005, 22 strains of Shigella spp. were isolated from the diarrheic patients in Seoul region. All of them were identified as S. flexneri by biochemical tests and serotyping. The prevalence of serotypes were variable by year, but the major serotypes were 2a and 3a. In an antimicrobial susceptibility test, all of the isolates were resistant to streptomycin and tetracycline, and susceptible to amikacin, kanamycin, cefoxitin, and gentamicin. All of the isolates showed the multi-resistant patterns over 3 drugs. By analysis of the plasmid profile the isolates were classified into 7 groups (P1~P7). Serotypes 2a and 2b were distributed to P1, P2, P3, and P4. Serotype 3a was differentiated to P5 and serotype 3b, to P6 and serotype 4a, to P7. PCR results showed that all isolates were positive for two virulence genes, ipaH and ial, but none of the strains had stx gene. The set1A and set1B genes were detected from 12 isolates (54.5%) that belonged to serotype 2a and 2b. The sen gene was detected from 19 isolates (86.4%). The 22 isolates showed 12 to 17 DNA fragments in the sizes ranging from 20.5 kb to 1135 kb, resulting in 13 patterns by the PFGE with Not I digestion. The PFGE patterns of the isolates showed the close relation with the serotypes, but no relations with year of isolation and antimicrobial resistance.

• Korean Journal of Environmental Biology
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• v.20 no.1
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• pp.91-99
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• 2002

With physico-chemical environmental factors such as temperature, DO, pH, conductivity and nutrients, size fractionated of phytoplankton standing crops and chlorophyll a concentrations $(>8\mu{m},\;3-8\mu{m},\;<3\mu{m})$ and their relationships were investigated at each station of Kyungan Stream and Togyo Reservoir from April to November in 1997. The two sampling sites showed different nutrient status: Kyungan Stream was eutrophic, while Togyo Reservoir was mesotrophic. Large sizes of phytoplankton and chl. a were higher in Kyungan Stream, opposite to those of Togyo Reservoir; Standing crops of phytoplankton $(>8\mu{m)$ and chl. a $(3-8\mu{m)}$ were high in Kyung-an Stream, while phytoplankton $(3-8\mu{m)}$and chi. a $(<3\mu{m)$ were abundant in Togyo Reservoir. These results imply that phytoplankton community in the highly eutrophicated water mainly comprised the large filamentous and/or colonial algae, such as Microcystis spp. and Aphanizomenon flos-aquae, which easily enriched by nutrients loading.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.333-340
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• 2010

This study was conducted to evaluate the microbial contamination levels in the processing company of Nuroong-ji. Microbial contamination levels were examined for sanitary indication bacteria such as aerobic plate count, coliforms and fungi, and pathogenic bacteria such as Escherchia coli O157:H7, Salmonella spp., Staphylococcus aureus, and Listeria monocytogenes. Contamination levels were detected differently according to handling materials and purposing work-space. The equipments and raw materials were not seriously contaminated but there were necessary to attend the cross-contamination. A high contamination level was detected at the process where the interference of the employees was relatively higher than the other process. Standardization of the roasting process (l20~$170^{\circ}C$, about 10 min) could be necessary to control the microbial organism effectively on Nuroong-ji manufacturing process. At small/medium size foodstuff manufacturers, it is the most important to improve the recognition level of individual hygiene but also expand a hygiene facility.

• Korean Journal of Food Science and Technology
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• v.33 no.3
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• pp.338-344
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• 2001

The effect of gamma-irradiation on the microbiological and general qualities of Kanjang (fermented soy sauce, Korean type) and Shoyu (fermented soy sauce, Japanese type) was studied. Samples were prepared, irradiated at 5, 10 and 20 kGy, and then stored at $25^{\circ}C$ for 18 weeks. The results showed that the Bacillus spp. was inactivated by 3 log cycles with the irradiation dose of 10 kGy and the number of Bacillus cells that survived from 10 to 20 kGy of gamma irradiation was decreased gradually during storage. Yeasts and Lactobacillus were nearly eliminated at 5 to 10 kGy of irradiation. The $D_{10}$ values of Bacillus, yeast and Lactobacillus in Shoyu were 2.67 kGy, 0.81 kGy and 1.30 kGy, in Kanjang were 2.75 kGy, 0.99 kGy and 1.47 kGy, respectively. The general quality of gamma irradiated Shoyu and Kanjang, such as total nitrogen, amino nitrogen, protease activity and pH were more stable than that of control during storage periods. Decolorization was observed just after irradiation, but the color was recovered during storage. The sensory evaluations showed that irradiated samples were more acceptable. Therefore, it was considered that gamma irradiation was effective for maintaining better quality of Shoyu and Kanjang during storage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.4
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• pp.295-306
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• 2004

Spatial patterns in the macrobenthic community structure in the inter- and subtidal zones in front of the Iwon Dike and environmental variables were examined in August 2001, In total, 156 macrobenthic species(123 intertidal species and 90 subtidal species) were recorded during this study, predominately polychaetes $(40{\%})$, bivalves $(22{\%})$, and crustaceans $(22{\%})$. Polychaetes made up less than $40{\%}$ of the intertidal communitr, but more than $50{\%}$ of the subtidal community. The mean density during this study was $1,456ind./m^{2}.$ Multivariate analysis (multidimensional scaling) revealed significant differences in community structure among four regions: near the Iwon dike (B1), the high and middle intertidal zone (B2), low intertidal zone (Al), and subtidal zone (A2). The number of species, total density, and diversity (H') varied significantly among the four regions. The distribution of macrobenthic community was affected by environmental variables, such as ${\%}$ silt/clay content, total sulfide, lose of ignition, and chemical oxygen demand. These environmental variables were negatively correlated with the dominant species (Nephtys polybranchia, Umbonium thomasi, and Scoloplos armiger) in the intertidal area, but positively correlated with the dominant species (Lumbrineris cruzensis, Notomastus latericeus, and Moerella sp.) in the subtidal area. Environmental variables $({\%}\;silt/clay content and total sulfide)$ were positively correlated with the dominant species (Heteromastus filiformis) in region Bl, but negatively correlated with the dominant species (Umbonium thomasi and Scoloplos koreanus) in region B2. Amphipods Urothoe spp. and Monoculodes koreanus were the dominant species in region Al. Umbonium thomasi, the dominant species in region B2, was not found in regions Bl or Al. We suggest that the inter-specific competition for territory and exposure to seawater may be important factors controlling the macrobenthic community structure in the inter- and subtidal zones in front of the Iwon Dike.

• ALGAE
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• v.29 no.2
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• pp.137-152
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• 2014

Mixotrophic protists play diverse roles in marine food webs as predators and prey. Thus, exploring mixotrophy in phototrophic protists has emerged as a critical step in understanding marine food webs and cycling of materials in marine ecosystem. To investigate the feeding of newly described mixotrophic dinoflagellate Ansanella granifera, we explored the feeding mechanism and the different types of species that A. granifera was able to feed on. In addition, we measured the growth and ingestion rates of A. granifera feeding on the prasinophyte Pyramimonas sp., the only algal prey, as a function of prey concentration. A. granifera was able to feed on heterotrophic bacteria and the cyanobacterium Synechococcus sp. However, among the 12 species of algal prey offered, A. granifera ingested only Pyramimonas sp. A. granifera ingested the algal prey cell by engulfment. With increasing mean prey concentration, the growth rate of A. granifera feeding on Pyramimonas sp. increased rapidly, but became saturated at a concentration of $434ngCmL^{-1}$ (10,845 cells $mL^{-1}$). The maximum specific growth rate (i.e., mixotrophic growth) of A. granifera feeding on Pyramimonas sp. was $1.426d^{-1}$, at $20^{\circ}C$ under a 14 : 10 h light-dark cycle of $20{\mu}Em^{-2}s^{-1}$, while the growth rate (i.e., phototrophic growth) under similar light conditions without added prey was $0.391d^{-1}$. With increasing mean prey concentration, the ingestion rate of A. granifera feeding on Pyramimonas sp. increased rapidly, but slightly at the concentrations ${\geq}306ngCmL^{-1}$ (7,649 cells $mL^{-1}$). The maximum ingestion rate of A. granifera feeding on Pyramimonas sp. was 0.97 ng C $predator^{-1}d^{-1}$ (24.3 cells $grazer^{-1}d^{-1}$). The calculated grazing coefficients for A. granifera feeding on co-occurring Pyramimonas sp. were up to $2.78d^{-1}$. The results of the present study suggest that A. granifera can sometimes have a considerable grazing impact on the population of Pyramimonas spp.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3578-3585
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• 2012

The purpose of this study was to establish the critical limit at CCP (Critical Control Point) of HACCP (Hazard Analysis Critical Control Point) system for instant noodle and it was conducted at P company in Ichen(Gyeonggi-do), Korea. According to the CCP, Fried process were experimented to removal and decrease of microbiological and chemical hazards by measuring of each temperature and times. As a result, the standard plate count and pathogenic microorganism were not detected by fried processing (Temperature : $145{\pm}10^{\circ}C$, Time : $75{\pm}30$ sec). The acid value of chemical hazards produced by fried processing was able to manage, showed lower (0.2) than the legal limit (0.6). Air-borne bacterial examination results detected(3 CFU/mL, 3 CFU/mL) in the Frying Room and Steam Room. Therefore, the CCP-BC of fried process would be a great alternative to prevent and remove hazard analysis, such as general and pathogenic microorganism (E. coli O157:H7, B. cereus, Listeria monocytogenes, Salmonella spp, Sthaph. aureus etc), chemical hazard analysis. In conclusion, it suggested that HACCP plan was necessary for management standard and systematic approach in establishement of critical limit, solving the problem, method of verification, education and records management by fried processing.